The present invention relates to a tool head and, more particularly, to a tool head for use with an automatic cable tie installation system providing improved performance and reliability.
As is well-known to those skilled in the art, cable ties are used to bundle or secure a group of articles such as electrical wires or cables. Cable ties of conventional construction include a cable tie head and an elongate tail extending therefrom. The tail is wrapped around a bundle of articles and thereafter inserted through a passage in the head. The head of the cable tie typically supports a locking element which extends into the head passage and engages the body of the tail to secure the tail to the head.
Although cable ties are often installed manually, it is desirable in certain applications to utilize an automatic cable tie installation system wherein cable ties are dispensed from a remote dispenser, and thereafter delivered to a tool head for application about a bundle of wires positioned within the jaws of the tool head. Automatic cable ties installation systems are well-known in the art, and are disclosed for example in U.S. Pat. Nos. 4,790,225 and 4,498,506. It will be appreciated that the disclosed tool heads include a plurality of subassemblies each having multiple moving parts, the subassemblies cooperating together to deliver, tension and cut the cable tie. To be commercially practical, the tool head must be capable of repeatedly applying a cable tie about the bundle of articles inserted within the jaw assembly without jamming. The tool head must also be able to complete a cycle (wherein one cable tie is wrapped, tensioned and cut) within a sufficiently short interval of time.
Those skilled in the art will appreciate that the foregoing requirements demand extremely accurate and precise location and support of the various cooperating components of the tool head. These prior art tool heads, including the tool heads disclosed in the mentioned patents, often locate and support many of the internal cooperating components via the housing shells. These housing shells are typically formed of plastic and are susceptible to flexing and twisting during operation which can adversely affect the cooperation between the components of the tool head, thus leading to jamming and/or failure of the tool head. Moreover, the practice of locating the various cooperating components of the tool head with respect to more than one reference structure (e.g., the two separate housing shells) allows the manufacturing tolerances associated with the individual components to be combined, which may lead to misalignment of the components.
There is therefore a need in the art for a tool head for use with an automatic cable tie installation system which exhibits improved reliability, and reduced jamming and/or failure. The improved tool head should maintain an accurate and precise relationship between the interacting and cooperating components of the tool head even when the tool head is subjected to such factors as flexing and twisting of the housing, thermal expansion and contraction of the housing, and operational wear.